1. Field of the Invention
The present invention relates to a portable computer and, more particularly, a portable computer using an auxiliary liquid crystal display panel having a touch screen as a pointing
2. Description of the Related Art
At the present time, portable computers such as a notebook computer, a laptop computer, and a palmtop computer have been widely used in various business fields.
Referring to FIG. 1, a conventional portable computer 10 is shown. Portable computer 10 includes a liquid crystal display (LCD) panel 12 and a body 14. The LCD panel 12 is hingedly coupled to the body 14. A central processing unit (CPU), a memory device, a disk drive, etc. are arranged in the body 14. A keyboard device 16 and a pointing device 18 are mounted upon the body 14. Recently, most portable computers also have adopted a touch pad as a pointing device.
Considering free movement and use, a portable computer can be beneficial for business use. In this regard, for situations where a customer consults with a business representative in a face-to-face manner, portable computers considering such situations have been provided. A portable computer having a rotary LCD panel, for example, can be desirable for use in business fields where such frequent consultation occurs. FIG. 2 illustrates a portable computer 20 having a rotary LCD panel 22. Referring to FIG. 2, LCD panel 22 of portable computer 20 is rotatively coupled to a body 24. With the LCD panel 22 rotated in the direction indicated by the circular arrow A, a user can operate the portable computer 20 using a keyboard device 26 and a pointing device 28 which are mounted upon the body 24.
FIG. 3 illustrates an example of using a portable computer 20 having the rotary LCD panel 22 shown in FIG. 2. As shown in FIG. 3, a business representative 30 can rotate the rotary LCD panel 22 toward a customer 35 so that the customer 35 can easily look at the rotary LCD panel 22 in a face-to-face consultation. Since the business representative 30 can show data to the customer 35 through a screen of the rotary LCD panel 22, the consultation can be carried out efficiently. However, the business representative 30 can have difficulty in directly looking at the screen of the LCD panel 22. When the business representative 30 indicates a specific portion of the screen (e.g., click a specific icon) or selects a menu of an application program using a pointer, operation can be difficult. However, if the portable computer 20 were to have an auxiliary screen which enables the business representative 30 to confirm a position of the pointer displayed on the LCD panel 22, the above-mentioned problems can be overcome.
U.S. Pat. No. 5,637,871 to Piety, et al., entitled Portable Digital Infrared Thermography System, discloses an infrared thermography system that automates the collection, display, analysis, annotation, and recording of thernographic data and facilitates generation of reports. The system includes an infrared camera and a digital video data collector (VDC) having an embedded PC with an internal hard drive. The VDC also includes a VGA color LCD display with touch screen overlay for displaying images, for presenting information to a thermographer, and for receiving data and command inputs from the thermographer.
U.S. Pat. No. 5,801,793 to Faris, et al., entitled Backlighting Construction For Use In Computer-Based Display Systems Having Direct And Projection Viewing Modes Of Operation, discloses a reconfigurable backlighting construction for use in portable computer-based systems having direct and projection viewing modes of operation. The backlighting construction is integrated with an LCD display panel, a micropolarization panel, and a touch-screen writing panel to provide several different types of portable computer-based systems including, for example, a portable notebook computer, a computer-driven image display device, and a portable pen-computing device.
U.S. Pat. No. 5,828,427 to Faris, entitled Computer-Based Image Display Systems Having Direct And Projection Modes Of Viewing, discloses an electro-optical backlighting panel construction for use in portable computer-based systems having direct and projection viewing modes of operation. The electro-optical backlighting panel is integrated with an LCD display panel, a micropolarization panel, and a touch-screen writing panel to provide several different types of portable computer-based systems including, for example, a portable notebook computer, a computer-driven image display device, and a portable pen-computing device.
U.S. Pat. No. 5,837,968 to Rohrberg, et al., entitled Computer-Controlled Modular Power Supply For Precision Welding, discloses a computer controlled modular power supply for precision welding that includes an enclosure which holds a computer control module, a welding power module and an electrical power module. The computer control module includes a microprocessor which is programmed using a color LCD display with a touch screen mounted on one side of the enclosure.
U.S. Pat. No. 4,846,694 to Erhardt, entitled Computer Controlled, Overhead Projector Display, discloses an apparatus for demonstrating the use of a computer terminal that includes a projection module supported on a standard overhead projector. The projection module includes a frame which is adapted to rest on an illumination window of the overhead projector. A transmissive liquid crystal display is mounted in the frame parallel to the illumination window such that an image on the liquid crystal display is projected by the projector. A transparent touch screen is also mounted in the frame overlying the liquid crystal display. By means of a stylus, a user touches the touch screen and thereby designates desired text and/or images for subsequent display. Coupled to the decoder is a computer which retrieves the desired text and/or images which are then transmitted to a display driver.
U.S. Pat. No. 5,633,660 to Hansen, et al., entitled Integrated Touch Screen Input Device, discloses an integrated input device. The integrated input device includes a contact sensor capable of producing an analog signal indicative of the location of the position which is touched, an A/D converter capable of receiving the analog signal output from the contact sensor and converting it to a digital signal, a computer capable of receiving the digital signal output from the converter, interpreting the digital signal and transmitting a digitized video signal in response to the digital signal, a video connector capable of receiving the digitized video signal output from the computer, and a display which is capable of receiving the output from the video connector.
U.S. Pat. No. 5,886,424 to Kim, entitled Power Supply Apparatus For Portable Computer And DC Input Selection Circuit Adapted To The Same, discloses a power supply apparatus which permits a docking station to be operated with battery power from a battery pack of a portable computer even if supply of AC power to the docking station is accidentally cut off. The apparatus for a portable computer system for use with a docking station having a logic circuit for expanding functions of the portable computer includes a DC input selection circuit placed on the portable computer side for switching between the first and second DC voltages to provide a switched DC voltage to the portable computer, as well as the docking station, so that the docking station is operated with the second DC power source even though supply of AC power to the docking station is cut off.
It is therefore a feature, among other features, of the present invention to provide a portable computer having an auxiliary display device which can confirm a position of a pointer and control the pointer when a user is unable to look at a screen of an LCD panel of the portable computer.
According to one aspect of the invention, a portable computer includes a main LCD panel hingedly coupled to a system body, an auxiliary LCD panel mounted upon the system body, a first video controller for supplying video data to the main LCD panel, and a second video controller for supplying the video data to the auxiliary LCD panel, so that a video image is identically displayed on both the main LCD panel and the auxiliary LCD panel.
The portable computer includes a touch screen mounted upon the auxiliary LCD panel, and a touch screen interface for converting an input signal of the touch screen into a pointer input signal. The touch screen is used for controlling a pointer.
The main LCD panel is rotatively coupled to the system body. The portable computer includes a rotation sensor that senses rotation of the main LCD panel to generate a rotation sense signal, and a microcontroller that selectively controls an on state and an off state of the auxiliary LCD panel in response to the rotation sense signal. The auxiliary LCD panel has a back light, and a Direct Current/Alternating Current (DC/AC) inverter that inverts Direct Current (DC) power supplied from a power supply into Alternating Current (AC) power suitable for the back light and, thereafter, supplies the inverted version of the DC power to the back light.
The keyboard device of the portable computer has a specific function key that selectively controls an on state and an off state of the auxiliary LCD panel, and a microcontroller that selectively controls an on state and an off state of the LCD auxiliary panel when the specific function key on the keyboard device is actuated.
According to another aspect of the present invention, a portable computer includes a main LCD panel hingedly coupled to the system body, an auxiliary LCD panel mounted upon the system body, a video controller for supplying video data to the main LCD panel, and a definition converter for inputting the video data supplied from the video controller and converting the video data so as to have a definition suitable for the auxiliary LCD panel, so that a video image is identically displayed on both the main LCD panel and the auxiliary LCD panel.